I use the Tamron 28-75 as my primary lens on an a A37. It's a little soft wide open, especially at the long end, but if you're not a pixel peeper I think you'll be pleased with the results. I mostly take portraits of my children and family members, so the focal range is perfect for me. I have never even once wished it were any wider. In good indoor light the focus is usually very quick and accurate, but a little loud. Let me know if you have any other questions about the combo, I'd be happy to answer them.